Summary A Boeing 737-200, registration C-FRYG, operated by Canada3000 Ltd., with 107passengers and six crew members on board, was on an instrument flight rules flight from Cayo Largo Del Sur, Cuba, to Montral/Mirabel International Airport, Quebec. About 20minutes after take-off, the flight crew noted fluctuating oil pressure in the right engine (PW JT8D-9A) and a low oil level indication. As a precaution, the crew shut down the engine, declared an emergency, and requested to divert to FortLauderdale Airport, Florida. When the aircraft was established in a holding pattern, the engine fire alarm sounded. Both fire extinguisher bottles were discharged in the right engine nacelle, but the fire did not go out. The pilot advised air traffic control of the situation and directed the aircraft toward FortLauderdale Runway27R. After landing, the aircraft stopped on the runway, and the aircraft was evacuated. The right engine was still on fire. Emergency services extinguished the fire, and no injuries occurred. Ce rapport est galement disponible en franais. Other Factual Information The Boeing 737-200, operating as flight CMM2226, took off from Cayo Largo Del Sur, Cuba, bound for Montral/Mirabel International Airport, Quebec, around 2320 Coordinated Universal Time.1 The first officer was the pilot flying in the right seat, and the captain was the pilot not flying. Around 2340, while the aircraft was climbing through 20000feet above sea level (asl), the flight crew noted that the oil pressure in the right engine was fluctuating and that the oil level was at 0.5gallon (USG). The oil temperature was high but below the maximum of 165C. At the time of departure from Cayo Largo, the oil level was between 3.5 and 4USG. At 2340, as a precaution, the engine was shut down and continued to windmill,2 following the Engine Failure/Shutdown checklist in the Quick Reference Handbook. The low-pressure compressor rpm was indicating 10percent, and the high-pressure compressor rpm was indicating 20percent. The aircraft was flying in Cuban airspace, about 20nautical miles (nm) west of Varadero/Juan Gualberto Gomez Airport,Cuba. The flight crew declared an emergency to Havana Control Centre and requested and was cleared to maintain 16000feet. Around 2350, radio contact was established with Miami Area Control Centre, Florida. The aircraft was identified by radar at about 6nm south of the TADPO intersection, which marks the boundary between Cuban and US airspace on air routeUG448. Around 2357, after requesting a weather briefing, the crew elected to continue to FortLauderdale, Florida, and requested that emergency services be put on standby for landing. At the request of the captain, flight CMM2226 was cleared for a holding pattern. The pattern was flown 20nm east of the JUMAR fix, which is 11.3nm east of the threshold of FortLauderdale Runway27R. When the aircraft was about to enter the holding pattern, a flight attendant entered the cockpit and advised the flight crew that some passengers had seen sparks under the right engine nacelle. The captain asked the flight director to confirm the information. A few minutes later, the flight director returned and confirmed to the captain that sparks could be seen. Suddenly, the following warning lights for the right engine came on: Dual Bleed, Oil Filter Bypass, and Start Valve Open. At that time, there were no indications of an engine overheating or an engine fire on any of the cockpit instruments. Except for the Dual Bleed warning light, the checklists for Oil Filter Bypass warning lights and Start Valve Open warning lights led the flight crew to perform the Engine Failure/Shutdown checklist. However, that checklist was already completed at 2340. The captain asked the flight director to prepare the cabin for an emergency landing, which he planned for within the next 20minutes. When the aircraft was established in the holding pattern, the Engine Overheat light came on. While the captain was executing the appropriate checklist, the Engine Fire Warning Switch light came on, and the fire alarm sounded. The captain completed the Engine Fire, Severe Damage or Separation checklist. One of the two fire extinguisher bottles was discharged inside the engine nacelle. Since the Engine Fire Warning light was still on, the second fire extinguisher bottle was discharged. It could not be determined when the first fire indication appeared but at 0043, the captain advised the arrival controller at FortLauderdale that he wanted landing priority because of an uncontrollable fire in the right engine. Meanwhile, the first officer directed the aircraft toward the airport, initiated the descent, and increased speed to about 324knots. During the approach, at about 3000 feet asl, the captain took the controls and landed the aircraft on Runway27R. After the aircraft came to a stop on the runway, the evacuation began. Most passengers were evacuated via the three emergency exits on the left side (L1, WE1, and L2). The right front door(R1) had been opened, and some passengers exited through that door, despite the fire on that side. Emergency services responded and put out the fire. The blaze was hard to extinguish because it was in the accessory gearbox, which is made of a magnesium alloy. When this material is burning, it is very hard to put out unless the correct extinguishing agent is used. The flight crew was certified and qualified for the flight, in accordance with existing regulations. The captain had 4485flying hours, including 2735hours as captain, of which 87hours were as captain on the Boeing737. The first officer had 4000flying hours, including 605hours as first officer on the Boeing737. Configuration of the aircraft for a landing with one engine out requires a higher-than-normal speed on the approach. When the engine was shut down, the aircraft weight was approximately 114000pounds, which is 11000pounds over the maximum certified landing weight specified by the manufacturer. Since C-FRYG was not equipped with a fuel jettison system, it would have had to fly for more than two hours with one engine out to reduce its weight below the maximum certified landing weight. Landing an aircraft with a weight exceeding the maximum certified landing weight is not prohibited in an emergency. Although the flight crew did not establish a specific target weight for the landing, they agreed to fly a holding pattern for about one hour to reduce aircraft weight while completing all pre-landing checks. The weather forecast for Varadero and Havana indicated a possibility of rain showers associated with storms, reducing visibility to 3km for the period from 1900 to 0200. The forecast for Miami and FortLauderdale called for rain showers but no storms. The Engine Failure/Shutdown checklist indicates the requirement to plan for a landing at the nearest possible suitable airport. Neither the Quick Reference Handbook nor the Boeing737 Operations Manual provides a definition for suitable airport. A definition for suitable airport exists, but it applies only to extended-range twin-engine operations (ETOPS), which was not the case with flightCMM2226. Appendix B of Transport Canada's publicationTP6327E, Safety Criteria for Approval of Extended Range Twin-Engine Operations (ETOPS), states that for an airport to be suitable, it must have the capabilities, services and facilities necessary to be designated as an adequate airport and have weather conditions and field conditions at the time of the particular operation which provide a high assurance that an approach and landing can be safely completed with an engine and/or systems inoperative, in the event that a diversion to an enroute alternate becomes necessary. The flight crew of CMM2226 determined that FortLauderdale Airport, despite not being the nearest, was the most suitable. The grounds cited were the following: confidence to obtain better air traffic services, weather conditions, familiarity with this airport and better support to the passengers. Continuing the flight allowed more fuel to burn and reduced the aircraft weight before landing. Continuing the flight also allowed more time to complete all the checks for a landing with one engine out. Because the right engine was windmilling, the flight crew had no reason to believe that its condition would deteriorate further. The engine fire detection system consists of a dual detector inserted in a sleeve, which is covered by a perforated metal shield. The detection system monitors the upper and lower parts of the engine and is wired in series. One detector senses high temperatures and the other detects fires. In the event of overheating, an amber light marked Engine Overheat comes on when the temperature sensor detects a high temperature of 400F. In the event of fire, a red light illuminates on the handle marked 1 (for the left engine) or 2 (for the right engine). The two main alarm lights also illuminate and a fire alarm bell sounds. The engine fire extinguishing system is a gaseous smothering system, designed to flood either engine cowling area with an inert gas. A switch for each engine in the cockpit electrically controls the fire extinguishing system. Each engine uses two extinguisher bottles containing 3.5pounds of halon pressurized with dry nitrogen. The flight crew can discharge either extinguisher bottle by selecting the applicable fire switch. The extinguishing agent is released through discharge diffusers installed above and at the centre of the engine. Sparks, observed by the passengers, are typical of a fire fuelled by magnesium. When magnesium burns, it generates its own oxygen. It is very difficult to put such a fire out with halon extinguishers. Once ignited, these alloys give off intense heat, and the fire is hard to control. The engine oil lubrication system consists of a high-pressure oil distribution system that supplies lubrication to the main bearings and various accessories. Oil flows down by gravity from the oil tank to the engine pump inside the accessory gearbox compartment. Oil is forced under pressure through an oil filter and proceeds to the fuel-cooled oil cooler. From there, the oil flows to various bearings in the engine. If the oil filter or the oil cooler becomes clogged, bypass valves in these components will open to allow oil to continue flowing through the system. An adjustable pressure control valve on the pressure side of the pump in the accessory gearbox maintains pressure and keeps oil flowing in the system by returning oil to the pump intake. Four scavenge pumps return oil from the bearing cavities to a sump in the accessory gearbox. From there, oil flows back to the oil tank again. A breather system links the engine bearing cavities, accessory gearbox, and oil tank to maintain proportional oil flow and to prevent cavitations of the pump during engine operation. According to information received from Canada3000, the oil level in the engines was adjusted during a stopover in Toronto, Ontario, on the day of the occurrence. The aircraft flew from Toronto to Cayo Largo via Montral without requiring any oil to be added. The carrier had been using Shell560oil, recommended by the engine manufacturer, for some time. The engine oil level on departure from Cayo Largo was about the same in both engines, that is, between 3.5 and 4USG. The journey logbook also indicates that one litre of oil was added to the constant speed drive of the right engine on three occasions: 06June2001, 12June2001, and 24July2001. The aircraft was built in accordance with Federal Aviation Regulations (FARs) Part25. FAR 25-1203(a) states that there must be approved, quick acting fire or overheat detectors in each designated fire zone, and in the combustion, turbine, and tailpipe sections of turbine engine installations, in numbers and locations ensuring prompt detection of fire in those zones. Model737-200 aircraft, including C-FRYG, were exempted from one provision of FAR25-1203(a), allowing an exemption from the requirement to have a fire detection system in the tailpipe section. This exemption did not play a role in this event, since the fire was not in the tail pipe section. FAR 25.1195(b) states that the fire extinguishing system, the quantity of the extinguishing agent, the rate of discharge, and the discharge distribution must be adequate to extinguish fires. It must be shown by either actual or simulated flight tests that under critical airflow conditions in flight the discharge of the extinguishing agent in each designated fire zone specified in paragraph(a) of this section will provide an agent concentration capable of extinguishing fires in that zone and of minimizing the probability of re-ignition. FAR 25-1197(a)(1) requires that the extinguishing agents be capable of extinguishing flame emanating from any burning of fluids or other combustible materials in the area protected by the fire extinguishing system. FAR25.1309(a)(1) and (2) state that the occurrence of any failure condition which would prevent the continued safe flight and landing of the airplane is extremely improbable and that the occurrence of any other failure condition which would reduce the capability of the airplane or the ability of the crew to cope with adverse operating conditions is improbable. Federal Aviation Administration (FAA) Advisory Circular AC20-135, entitled Powerplant Installation and Propulsion System Component Fire Protection Test Methods, Standards and Criteria describes the test performed to certify magnesium parts. The parts must be fireproof or fire resistant. To qualify as fireproof, each part must be able to withstand a temperature of 2000F for at least 15minutes. To qualify as fire resistant, materials must withstand a temperature of 2000F for at least five minutes. C-FRYG was equipped with a cockpit voice recorder (CVR) and a flight data recorder (FDR). The CVR is a Fairchild modelA100A, part number93-A100-80, serial number56480. The FDR is an Allied Signal model980-4100-GMUN 11, serial number10582. Both recorders were sent to the TSB Engineering Laboratory in Ottawa. The CVR was analysed but yielded no information; power to the aircraft was cut off after the occurrence, and when it was restored later, the messages were recorded over. Since the CVR retains only the last 30 minutes of the flight, conversations during the occurrence flight could not be played back. The FDR records 11parameters, but only one engine parameter.3 The FDR revealed that the right engine was shut down 27minutes after engine startup, which is about 20minutes after take-off. It was only on 08 August 2001, four days after the occurrence, that TSB took charge of the investigation, in accordance with Annex13 of the Convention on International Civil Aviation and following discussions with the US National Transportation Safety Board (NTSB). Teardown of the engine took place at New Jet Engine Services in Miami from 14 to 16August2001 inclusive, in the presence of the NTSB, the aircraft manufacturer (Boeing), the engine manufacturer (Pratt Whitney), Transport Canada, and a representative of the carrier (Canada 3000). The analysis focussed on the causes of the loss of oil and of the fire that started about one hour after the engine was allowed to windmill. The right engine on C-FRYG was a model JT8D-9A, serial number666715, built by Pratt Whitney. It had accumulated 44961hours and 36031cycles since new. The engine had accumulated 3817hours and 2459cycles since the last inspection of the engine's hot section on 20September1999. Records show that, during that inspection, the accessory gearbox and the high- and low-pressure turbines were inspected visually. The high- and low-pressure compressors, the diffuser and combustion sections, and the exhaust section were repaired. The engine was imported to Canada and leased to Canada3000. It was installed on aircraftC-FRYG on 11December2000. The post-occurrence engine teardown revealed the following: The starter was found intact and hanging from the start valve; it had burn marks on the outside and could not turn freely. The pressure side of the breather tube for the No.4bearing housing was partly clogged with coke residue, and the pressure side of the breather tube for the No.4bearing inside the diffuser was completely clogged with coke residue. The end of the breather tube associated with the No.4bearing was also clogged. External surfaces of the high- and low-pressure turbine shafts exhibited blackening and discolouration. The No.1bearing was intact and wet with oil; several rollers in the bearing exhibited bluish colouration. The No.3bearing was intact and turned freely, but the oil in the bearing housing felt sticky. The No.5bearing was intact and wet with oil and turned freely; the rollers in the bearing showed light wear near the centre, as indicated by a change in colour from gold to silver. All other bearings were intact and showed no signs of damage. The left side of the accessory gearbox was consumed by fire from the centre of the fuel pump to the starter mounting bracket, exposing the internal gearing and the oil filter. The centre bracket, the left side bracket, the starter mounting bracket, and the oil tank in the accessory gearbox were all consumed by fire. Paint on the exterior of the gearbox casing was blistered. The de-oiler was separated from the accessory gearbox, severely burned and damaged. A portion of the outer casing was missing. The shaft between the high-pressure compressor and the accessory gearbox was intact. The oil-fuel cooler was tested for leaks. All oil-side components of the cooler must withstand a pressure of 200 pounds per square inch (psi). All fuel-side components must withstand 1000psi for 5 minutes. During the test, the oil side showed a drop in pressure to 5psi, and the fuel side showed a drop in pressure to 2psi. Both O-rings were hardened but intact, and the outer surfaces were flattened. A review of the report on limited life components revealed that none of them had exceeded their life cycle. The accessory gearbox was sent to the TSB Engineering Laboratory to determine the cause of the fire. Because of the condition of the parts, the analysis yielded no information.